1621793856 has 28 divisors (see below), whose sum is σ = 4290996752. Its totient is φ = 540597888.

The previous prime is 1621793839. The next prime is 1621793911. The reversal of 1621793856 is 6583971261.

It is a super-2 number, since 2×1621793856² = 5260430622718697472, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4223230 + ... + 4223613.

It is an arithmetic number, because the mean of its divisors is an integer number (153249884).

Almost surely, 2^1621793856 is an apocalyptic number.

1621793856 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

1621793856 is an abundant number, since it is smaller than the sum of its proper divisors (2669202896).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1621793856 is an equidigital number, since it uses as much as digits as its factorization.

1621793856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8446858 (or 8446848 counting only the distinct ones).

The product of its digits is 544320, while the sum is 48.

The square root of 1621793856 is about 40271.5017847609. The cubic root of 1621793856 is about 1174.8936329850.

The spelling of 1621793856 in words is "one billion, six hundred twenty-one million, seven hundred ninety-three thousand, eight hundred fifty-six".